Elecom製の激安NAS[NSB-3NR series]のopkgパッケージをバックアップした ref: https://qiita.com/nsmr0604@github/items/e4d8fc20cd0b5a914a28

mkPkg

#!/bin/sh
# start script use busybox.
# set env
#PKGINFO=/var/lib/dpkg/info
PKGINFO=/usr/lib/opkg/info
PKGNAME=$1.pkg
PKGVER=_$3
[ $PKGVER != _ ] && PKGNAME=$1$PKGVER.pkg
WORK=/tmp/$1.work
# mkdir work dir
mkdir -p $WORK/control.d
mkdir -p $WORK/data.d
# copy control and script
for file in $(ls $PKGINFO/$1.*) ; do
cp $file $WORK/control.d/${file##*.}
done
# copy files from list
while read line ; do
[ -d $line ] && continue
[ ! -d $WORK/data.d${line%/*} ] && mkdir -p $WORK/data.d${line%/*}
cp $line $WORK/data.d$line
done < $WORK/control.d/list
# pack data.tar.gz
tar -C $WORK/data.d -czf $WORK/data.tar.gz .
rm -rf $WORK/data.d
# pack control.tar.gz
rm $WORK/control.d/list
tar -C $WORK/control.d -czf $WORK/control.tar.gz .
rm -rf $WORK/control.d
# make package
echo '2.0' > $WORK/debian-binary
cd $WORK && ar -r $PKGNAME debian-binary control.tar.gz data.tar.gz && cd $OLDPD
# copy package to current
cp $WORK/$PKGNAME $PWD/
# delete work dir
rm -rf $WORK
# end script
exit 0

stdout

root@NAS:~# which sh
/usr/local/xbin/sh
root@NAS:~# sh --help
BusyBox v1.28.1 (2018-02-15 14:34:02 CET) multi-call binary.

Usage: sh [-/+OPTIONS] [-/+o OPT]... [-c 'SCRIPT' [ARG0 [ARGS]] / FILE [ARGS]]

Unix shell interpreter
root@NAS:~# opkg list-installed | xargs -n 3 mkPkg
    (省略)
root@NAS:~# ls nasmiru*
nasmiruagentD_1.0-1.pkg
root@NAS:~#